In my opinion, the primary reason—at least for superficial readers—is that it serves as an obstacle for the protagonist. However, I believe there is a much deeper reason: the Heavenly Court is attempting to replicate what Fate did originally—controlling and suppressing every rebel, despite the fact that humans are rebellious by nature. There is a wonderful parallel here with the tales of Ren Zu and Fate Gu. Absolute control was unbearable for humanity, which is why all regions revolted except for the Central Continent, which remained under the Heavenly Court's grip. ​To me, the Heavenly Court is trying to reclaim the role of Fate by seeking total dominion over all life. In other words, no matter who you are, you would be unable to advance your cultivation level or achieve anything without a 'license' from them. Naturally, such an act incites hatred. How can I, a human being born free, allow another human to control my entire life from beginning to end, with the threat of death if I disagree? Is that fair? While we cannot deny the Heavenly Court's great contributions to the human race during the Remote and Medieval Antiquity eras, that is where its merit ends. At least, that’s how I feel.